1. Field of the Invention
The present invention relates to fish processing and more particularly to an improved method and apparatus for processing a fish body that has been cut into a plurality of transverse fish body sections, and more particularly relates to an improved imaging apparatus that features imaging of both sides of a transverse fish slab section using automated illumination and background screening to produce an improved image of each of the opposed sides of a fish body section.
2. General Background
In the processing of fish such as tuna, it is common to freeze a catch of fish at sea, and to process the catch on shore. The processing normally involves thawing the fish followed by manual operations of slicing the fish belly and the removal of viscera. The visceral cavity is then washed with water, and the tuna inspected for spoilage. The tuna is then usually cooked whole in a batch type precooking operation.
Manual prior art methods of processing tuna are described in greater detail in U.S. Pat. No. 3,594,191 issued to J. M. Lapeyre. The '191 Lapeyre patent discloses the concept of cutting the tuna in lateral sections at spaced intervals and thereafter separating the edible loin portions to provide discrete cannable portions.
A later U.S. Pat. No. 3,593,370 entitled "Method of Butchering Tuna" issued to J. M. Lapeyre, describes a method for processing such transverse tuna sections while frozen. The method of butchering frozen tuna described in the '370 Lapeyre patent includes the subdivision of the whole fish into a plurality of transverse cross-sections and subsequently subdividing the cross-sections into frozen segments. The junctures between the segments are along lines generally parallel to the longitudinal axis of the fish and to the backbone thereof. Each lateral fish section is skinned and the skinned sections operated on to effect a separation of the scrap parts of the segments from the loin meat parts, while the latter were still in at least a partially frozen condition.
U.S. Pat. No. 3,800,363 issued to J. M. Lapeyre entitled "Tuna Butchering Method and System" describes an automated butchering method and system for separating the edible loin portions of transverse tuna slices provided by subdivision of a frozen whole tuna.
Three additional, more recently issued U.S. Patents include U.S. Pat. No. 4,748,724, entitled "Support Apparatus For Use In Video Imaging And Processing Of Transverse Fish Sections," U.S. Pat. No. Re. 33,917, entitled "Support Apparatus For Use In Video Imaging And Processing 0f Transverse Fish Sections," and U.S. Pat. No. 5,181,879, entitled "Method And Apparatus For Processing Fish Into Transverse Sections."
U.S. Pat. Nos. 3,593,370; 3,594,191; 3,800,363; Re. 33,917; 4,748,724; and 5,189,879 are each incorporated herein by reference.
A problem encountered in the cutting of transverse sections (such as transversely cut fish) with a robotic knife that tracks according to a video image is precision. Precision is required to separate fish bones, blood meat, visceral and like non-edible portions from the edible portions if waste is to be minimized. Therefore, there is a need for an improved, precise video imaging system that can precisely process the section with minimum waste.